Research

Energy balance

Zero-calorie alternate-day fasting (ADF) produces weight loss and metabolic improvements equivalent to moderate daily caloric restriction (CR) over 8 weeks, with a higher estimated energy deficit but similar absolute weight loss.

If you struggle with daily calorie counting, try alternating between eating normally and fasting (water/broth only) every other day. This pilot study suggests it works just as well as eating slightly less every day, without increasing the risk of regaining weight. Start with a test fast day to see if you can handle it.

ModerateSupportsMEDIUM confidence
Results suggest zero-calorie ADF is safe and tolerable, and is equivalent to moderate CR in producing short-term weight loss and improving body composition and metabolic parameters.
Victoria A. Catenacci et al. · Obesity · 2016

Why this rating

Randomized pilot study, small sample size (n=26), short duration (8 weeks).

Source

A randomized pilot study comparing zero‐calorie alternate‐day fasting to daily caloric restriction in adults with obesity

Victoria A. Catenacci et al. · Obesity · 2016

DOI 10.1002/oby.21581

rct · n=26Cited 327×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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